\section*{Ex. 1}

Given the file \texttt{bn-nobisection.cpp}, that explains how to implement a
robust method
\begin{enumerate}

    \item write and insert a \cpp{bisection} function, that implements the
    bisection method and will be used as low order method.

    \item complete the \cpp{robust} function so that it calls \cpp{bisection}
    first and \cpp{newton} afterwards.

    \item use the code to compute the zero of the function
       \begin{equation*}
         f(x) = x^2 - 0.5
       \end{equation*}
       in the interval $(0, 1)$ with the robust method.

\end{enumerate}
